Acute hepatopancreatic necrosis disease (AHPND) was first reported in China in 2009 and afterwards in Mexico in 2013. AHPND is caused by Vibrio parahaemolyticus and affects Penaeus monodon and ...Litopenaeus vannamei shrimp cultures. The bacterium contains the pirA‐ and pirB‐like genes in 69‐ to 70‐Kb plasmids, which encode the toxins that produce the disease. The aim of this study was to determine whether pirA‐ and pirB‐like genes existed in bacterial genera distinct from Vibrio before the first cases of AHPND were documented in Mexico. Two bacterial isolates were selected from shrimp farms in Nayarit in 2006 and analysed by nested‐PCR to determine the presence of pirA‐ and pirB‐like genes. The two isolates chosen did indeed show the presence of these genes, and those findings were confirmed by sequencing. Both strains matched to the bacterial species Micrococcus luteus. Results revealed two important situations: (a) the pirA‐ and pirB‐like genes were present in a bacterial species that has not been reported previously (Micrococcus luteus); and (b) pirA‐ and pirB‐like bacterial genes were present in Mexico before the first AHPND outbreak was reported in China.
Early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND), results in significant mortality in penaeid shrimp aquaculture. AHPND is caused by toxins secreted by pathogenic ...strains of Vibrio parahaemolyticus, that have acquired a unique 63–70 kb AHPND-associated plasmid (pVA1). This plasmid encodes the binary PirA/BVP toxins that consist of two subunits PirAVP and PirBVP. Consequently, the degradation of these toxins might be a valid strategy to control or mitigate AHPND. There is literature-based evidence that the application of Bacillus improves shrimp survival upon challenge with pathogenic V. parahaemolyticus. In this study, Bacillus subtilis DSM33018 strain was shown to degrade AHPND toxins in vitro, as detected by Western blots. Further, an in vivo challenge test, using gnotobiotically cultured brine shrimp Artemia franciscana exposed to PirA/BVP toxins, the DSM33018 Bacillus strain could completely alleviate toxicity. This finding indicates that mitigation of AHPND might include Bacillus-based degradation of PirVP toxins.
•This is the first scientific evidence on AHPND toxin degradation by Bacillus strains.•PirBVP is more susceptible to degradation by Bacillus strains than PirAVP.•PirA/BVP-induced mortality in Artemia can be mitigated by certain Bacillus strains
Acute hepatopancreatic necrosis disease (AHPND) is a bacterial disease associated to severe mortality in farmed shrimps, and caused by Vibrio parahaemolyticus containing plasmid pVA-1 encoding pirA ...and pirB toxins. This study investigates the presence of Vibrio spp. carrying plasmid pVA-1 in post larvae and juveniles Penaeus vannamei from farms located in Costa Rica. Moreover, a possible corelation between Vibrio spp. presence, management parameters, and water quality was also investigated. Between 2017 and 2018, post larvae, the first water pumped into ponds, and juvenile shrimp (6 to 7 weeks after stocking) were collected from 15 farms located in the Gulf of Nicoya and the country's Central Pacific region. On the day when the juvenile shrimp were collected, a survey was applied to farmers to obtain information about management conditions, finally physical-chemical parameters of pond water were measured. Plasmidic pVA-1 pirA and pirB genes were detected in hepatopancreas of juvenile shrimp in 5 (33.3%) farms, while Vibrio spp. were found in 6 (40.0%) farms. Sequencing of pVA-1, pirA and pirB genes showed 99–100% similarity to pathogenic Vibrio parahemolyticus XN89 homologous genes identified in Vietnamese shrimps. Statistically significant differences were found in the water volume (p < .03), rate of water replacement (p < .04), and farms disease history (p < .05). A correlation between presence of Vibrio spp. and water quality was not established. The molecular diagnosis of Vibrio spp., the plasmid and the genes encoding toxins that are associated with AHPND are reported for the first time in Costa Rica. Further studies aimed to isolate AHPND-causing Vibrio spp. from ponds, to generate histopathological data, and to establish economic losses due to AHPND mortalities in Penaeus vannamei farms, are needed to clarify the role and pathogenic features of Vibrio spp. in AHPND.
•Molecular detection of Vibrio spp. is reported for the first time in 40.0% of shrimp farms•Plasmidic pVA-1 and pirA/pirB genes associated to AHPND were detected in 33% of farms•pVA-1 was found in hepatopancreas of juvenile shrimp•Correlation between presence of Vibrio spp. and water quality was not established.•Statistically significant differences were found in the water volume, rate of water replacement, and farms disease history.
This study aimed to detect the presence of quorum-sensing (QS) signalling molecules and evaluate the in vivo virulence gene expression in shrimp challenged with acute hepatopancreatic necrosis ...disease (AHPND) positive Vibrio isolates. Three types of QS signal molecules, namely N-acyl-homoserine lactone (AHL), Autoinducer-2 (AI-2) and Cholerae autoinducer-1-like (CAI-1) molecules were detected in AHPND causing isolates using Agrobacterium tumefaciens KYC55, Vibrio campbellii JMH597 and V. campbellii JAF375 biosensors respectively. The presence of QS genes in all the 12 AHPND positive isolates was further justified by conducting molecular screening of the QS-related genes, luxR and luxS. Challenged groups demonstrated a significant (P < 0.05) increase in the expression levels of the QS master regulator gene luxR compared with the unchallenged group. The expression of pirA-, pirB-, toxR- and luxR genes peaked at 36 h in shrimp challenged with AHPND positive Vibrio parahaemolyticus BpShHep31 and V. harveyi BpShHep24. However, compared to the group challenged with V. parahaemolyticus BpShHep31, the V. harveyi BpShHep24 challenged group demonstrated 45.1-, 126.0-, 19.7- and 10.7- fold higher expression of pirA, pirB, toxR and luxR respectively.
•The autoinducer-1 (AI-1) and autoinducer-2 (AI-2) are the major quorum sensing signals produced by the AHPND isolates.•Expression level of pirA-, pirB-, luxR- and toxR- regulated virulence genes increased proportionally with high mortality rates in the shrimp challenged with AHPND positive isolates.•Up-regulation of the production capacity of pirA, pirB, toxR and luxR were observed at 36 h.
This essay emphasizes the founding values of Mediterranean Europe understood as a demo- cratic community of persons. In particular, the Author moves from Jacques Maritain’s thought and from the idea ...of European federalism in order to point it out that Europe, thanks to the ‘human bridges’ of Giorgio La Pira, can be not only an economic union, but also and above all a human community founded upon the respect and dignity of the person. From these values derive true democracy and protection of human rights which represent the essential core of Mediterranean Europe.
A major therapeutic goal in the treatment of multiple sclerosis (MS) is to prevent the accumulation of disability over an often decades-long disease course. Disability progression can result from ...acute relapses as well as from CNS intrinsic parenchymal disintegration without de novo CNS lesion formation. Research focus has shifted to progression not associated with acute inflammation, as it is not sufficiently controlled by currently available treatments. This review outlines how recent advances in the understanding of the pathogenesis of progressive MS have been facilitated by the development of more precise, less static pathogenetic concepts of progressive MS, as well as by new techniques for the analysis of region-specific proteomic and transcriptomic signatures in the human CNS. We highlight key drivers of MS disease progression and potential targets in its treatment.
This article addresses the scholarly debate over sectarianism and the Provisional Irish Republican Army's (PIRA) campaign during the Northern Ireland Troubles. It argues that although there is much ...merit in the contributions made in this discourse, unfortunately, for, the most part, there is a lack of engagement with the deeper meaning of sectarianism. Consequently, it seeks to enhance the understanding of sectarianism within this arena before considering the nature of the PIRA campaign. By conducting a thorough analysis of the killings conducted by this organisation in the early years of the conflict it is ultimately concluded that, at the very least, PIRA tolerated, and likely sanctioned, sectarian violence from within its ranks.
I processi di trasformazione che hanno interessato il campo fumettistico al crocevia del secolo si allacciano strettamente alla digitalizzazione e all’integrazione del sistema mediale. Accanto ...all’affermazione del graphic novel, che permette al fumetto di convergere verso archi narrativi organici di matrice romanzesca, si delineano tendenze al riscatto dei generi brevi del fumetto classico: la striscia umoristica, la vignetta fulminante, la tavola autoconclusiva. L’accrescimento vertiginoso dei flussi sviluppati dal web favorisce la trasposizione, il ricircolo, la stratificazione di simili schegge fumettistiche, tra comunicazione analogica e comunicazione digitale. Si tratta di proposte che insorgono dal basso, da protagonisti della compartecipazione creativa socialmediale o da rinnovatori della cultura underground. L’intreccio fra interazione estetica istituzionale e medialità autogestita, pur vincolato all’oligopolio delle piattaforme, dischiude originali opportunità di differenziazione e arricchimento dell’esperienza fumettistica.
Matthiola incana is a popular winter-flowering plant, and white is considered a valuable flower color for marketed cultivars. In this study, we aimed to identify the genes responsible for white ...flower coloration in six commercial cultivars of M. incana used as cut and potted flowers. The expression levels of chalcone synthase, flavanone 3-hydroxylase, flavonoid 3'-hydroxylase, dihydroflavonol 4-reductase, anthocyanidin synthase (ANS), and anthocyanidin 3-O-glucosyltransferase in the petals of ‘Kiss me White’ and ‘Pygmy White’ were 0%–48% lower than those in the purple flower ‘Vintage Lavender’, whereas the expression level of basic helix-loop-helix 2 (bHLH2) was two-fold higher. Significantly reduced expression levels of ANS were also detected in four other white flower cultivars: ‘Vintage White’, ‘Iron White’, ‘White Wonder No. 2’, and ‘Quartet White’. All investigated white flower cultivars had a single nucleotide deletion in the first exon of ANS, which we designated as ans-1. This generates a frameshift mutation and a nonsense codon. In addition to ans-1, ‘Kiss me White’ and ‘Pygmy White’ have a 481-bp insertion within bHLH2. This insertion has features of hAT-type transposable elements and was designated as dTmi1. All white flower cultivars contain the ans-1 mutation, whereas ‘Kiss me White’ and ‘Pygmy White’ are double mutants containing both bhlh2dTmi1 and ans-1. ‘Kiss me Yellow’, which accumulates carotenoids, but not anthocyanins, in its petals possesses the bhlh2dTmi1 allele, but not the ans-1 allele. Therefore, either bhlh2dTmi1 alone or ans-1 alone can lead to a deficiency in anthocyanin production in commercial cultivars of M. incana. We also developed co-dominant DNA markers that can distinguish between wild-type and mutant alleles of both bHLH2 and ANS. In combination with other previously developed markers that can distinguish between single- and double-flowered individuals, these markers will be useful for nursery plant management and breeding of commercial M. incana.
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